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प्रश्न
For a bivariate data, `bar x = 53`, `bar y = 28`, byx = −1.5 and bxy = −0.2. Estimate y when x = 50.
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उत्तर
Given:
`bar x = 53`,
`bar y = 28`,
byx = −1.5 and
bxy = −0.2
Regression equation of y on x is,
y = a + byx . x
byx = −1.5
`a = bar y − b_(yx) . bar x`
= 28 −( −1.5)53
= 28 + 79.5
= 107.5
∴ y = 107.5 − 1.5 x
i.e. y = −1.5 x + 107.5
Put x = 50
∴ y = −1.5(50) + 107.5
∴ y = −75 + 107.5
∴ y = 32.5
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